Remove the unused attribute const arch_env_t *arch_env from struct draw_chordal_env_t.
Remove the unused attribute const arch_env_t *arch_env from struct draw_chordal_env_t.

[r22752]

davidgiven/libfirm,8l/libfirm,8l/libfirm,davidgiven/libfirm,killbug2004/libfirm,8l/libfirm,killbug2004/libfirm,MatzeB/libfirm,killbug2004/libfirm,libfirm/libfirm,jonashaag/libfirm,libfirm/libfirm,davidgiven/libfirm,killbug2004/libfirm,libfirm/libfirm,davidgiven/libfirm,MatzeB/libfirm,jonashaag/libfirm,jonashaag/libfirm,davidgiven/libfirm,davidgiven/libfirm,libfirm/libfirm,jonashaag/libfirm,MatzeB/libfirm,8l/libfirm,jonashaag/libfirm,MatzeB/libfirm,MatzeB/libfirm,jonashaag/libfirm,killbug2004/libfirm,8l/libfirm,davidgiven/libfirm,killbug2004/libfirm,libfirm/libfirm,killbug2004/libfirm,MatzeB/libfirm,MatzeB/libfirm,8l/libfirm,jonashaag/libfirm,8l/libfirm